You can usually see the blood line, like in a dogs toe nails. Or our finger nails even. It is more difficult in dark beaks, just as it is more difficult to see the blood line if a dog has dark toenails.
I don't blame you I would be such a "chicken" about this if I couldn't tell for sure. So much a bigger deal than toe nails.
The line is easier to see with good light. in your photo it looks to me like it's about half way up to the dark section. At first I though it was right where the dark part starts but in the next photo it lok more like it's half way up the beak. Wish I could be more sure. Maybe you could slowly file if the bird would let you?
Good luck.